Governor for tube cleaner motors



Dec. 27, 1938; I P, E GOOD 2,141,182

GOVERNOR FOR TUBE CLEANER MOTORS Filed June 5, 1937 4 Sheets-Sheet 1 Dec. 27, 1938. P. E. GOOD GOVERNOR FOR TUBE CLEANER MOTORS Filed Jun e 5, 1937 4 Sheets-Sheet 2 Dec. 27, 1938 5 GOOD GOVERNOR FOR TUBE CLEANER MOTORS 4 SheetS -Sheet 3 Filed June 5, 1937 MK \Mu r/dl-E? V4 n Ill VIII-=12 WN MWN P. E. GOOD GOVERNOR FC JR TUBE CLEANER MOTORS Dec. 27, 1938.

Filed June 5, 1957 4 Sheets-Sheet 4 Patented Dec. 27,1938

, I oovmmoa roarusncmsmamoroas Paul E.-Good,'mverton, N. .I. I I ism...- June 5. 1m, Serial No. 146,673

Thisinvention relates to tube cleaner motors, and moreparticularly to a means for governing such motors. v

Tube cleaners as employed in the removal of I scale from boiler tubes necessarily involve the use of a motor of extremely small size and, accordingly, offer extreme difliculty in the provision of governing mechanism for controlling the speed of operation; so much so, in fact. that despite II the fact thatgoverningof the speed is substan tially essential, no present-day tube cleaner has been governor-equipped, .the sole method of speed control being either through manual control -of fluid delivered to the motor or by crowding or retarding the rate of feed or the motor through the tube so that the scale, acted upon by the motor driven cleaning elements,

itself acts as a brake to keep the operation of the a motor within reasonable speed limits. Obviously,

2 either method is unsatisfactory, for manual throttlingof a supply to a hose which is being hand fed through a tube, means that the control valve must be located at the end of the tube and, accordingly, presents dlfliculties as to accessi- 26 bility. Furthermore, since theoperator has no way of knowing the rate of scale variation through a given tube, he is only warned of excessively speeded up or retarded action on the part of the motor through transmitted sound.

The delay in eflecting a control may cause serious injury to he tube before the speed can-be properly'reguiated. The irregularityof the scale, obviously. also presents dimculty in control of the speed of the motor through controlling. the speed 35 of feedof the cleaner through the tube since a heavy patch of scale may be immediately succeeded by a light patch, or vice versa, with the result that the motor suddenly speeds up. or is suddenly retarded or even stopped. The dif- 4 ilculties arisingfrom the conditions just recited are, accentuated by the fact that the motor is necessarily small, and because of its type makes excessive demands upon its air supply necessitating large ports In addition to the damage caused to the motor .or tubeby the uncontrolled actionof the motor, "such action is in many cases extremely dangerous. The cleaners'employedon themotor are ilexibly coupled to the motor so that they may 50 be movedradially of the tube, and obviously, it I through carelessness, as often happens, vthe cleaner is projected from-the far end of the tube, there'isno resistanceto the pivotal swing of the cleaner'cl ments which spread radially causing considerable damage in their own vicinity and in many cases breakingfrom their moorings and injuring workmen ata distance.

The-principal reason why such motors have not been equipped with governors has been the absence of a compact governor construction which 5 lends itself to use in the motor. Since such 'motors must be of short length to enable their passage about curves in the tubes being'cleaned, any material increase in the length thereof will, obviously, result in a decrease in usefulness since, with the increased length the motor becomes unuseabie in tubes having bends of certain radius. Accordingly, the primary objects of this invention are the production of a governor-consum tion which may m very readily adapted to the present-day tube cleaning motors without materially varying the construction thereof or adding to their length, which may be very cheaply manufactured and readily assembled, and which at the same time will be suihciently to accurate in its operation to insure maintenance of the motor speed within given predetermined limits.

, These and other objects I attain by the construction shown in the accompanying drawings wherein, for the purpose of illustration I have shown a preferred embodiment of my invention and wherein:

Fig. 1 is a perspective view showing a tube cleaner motor. constructed in accordance with my invention;

Fig. 2 is a longitudinal sectional view through a preferred form of the motor;

Figs. 3, 4 and 5 are sections on lines 3-4, 4-4, and 5,-! respectively of Fig. 2; 5 Fig. 6 is a side elevation of the motor shaft; Fig. 7 is an end elevation thereof illustrating the governor-mounting;

Fig. 8 is a side elevation of the removable portion combining with the head to mount the governor va1ves;-

Fig. 9 is a combined perspective of the sections of the governor valve; 7

Fig. 10. is a detail sectional view through the. valve; I

.Fig. 11- is a fragmentary sectional view showing a modified form of the invention;

Fig. 121s a side elevation of a portion of the motorfshaft showing the governor-construction of Fig. 11,; V Figs. 13 and 14 are sections on lines ll-H and ll-il respectively of Fig. 11;

Fig. '15 is a section on line lB-li of Fig. 14; Fig. 16 is a fra mentary sectional view of a further modified form, of the invention;'

Fig. 17 is a detail view of the governor end of the shaft in the form of the invention shown in Fig. 16;

Figs. 18 and 19 are sections on lines |8-|2 and |2|2 respectively of Fig. 16;

Fig. 20 is an elevation of the shaft head in the form of the invention shown in Figs. 16 to 19; and

Figs. 21 and 22 are combined views showing diiIerent sets of springs which can.be employed in the form of invention shown in Figs. 1 to 15 in order to secure graduated port closing in the governor mechanism.

Referring now more particularly to the drawings, the numeral ill generally designates a casing divided by a partition into motor and inlet chambers II and I2. The motor at present illustrated is of the sliding vane type. comprising an eccentrically disposed. cylinder l2 the wall of which is formed with intake and exhaust ports l4 and II, of-which the intake ports are surrounded exteriorly of the cylinder by an inlet conduit ii. The exhaust ports communicate with passages l1 formed in the cylinder casting which passages are maintained in alignment with openings in a thrust-washer l2 and the forward end of the casing by a dowel IS. The rotor-body 22 in the cylinder has theusual sliding vanes 2| provided in this type of motor, and, at its forward end, has an extension 22 projecting through thrust washer I8 and a bushing 22 carried by the casing to the exterior of the casing at which point it is provided with a suitable connecting means 24 for an operating head 25. At its rear end, the rotor body 20 is provided with an extension 22 projecting through a split thrust-washer 21 and bushing 28, the latter being held in position through a threaded locking ring 29. The split washer 21 and bushing 28 are held against rotary movement with relation to the cylinder by the hereinbefore mentioned dowel l2, and are provided with aligned openings registering with inlet conduit l6, that of the bushing being indicated at 2|! in Fig. 4. The structure so far described is common to all forms of the invention herein illustrated.

outwardly of the bushing, the shaft extension 22 is provided with an enlarged head 2| bearing against bushing 22. A head of this character is provided in the usual structures and is, in accordance with my invention, slightly modified to incorporate the govemor-structure. In the form at present under discussion; an extension 22 for the head is secured to the head by bolts 22 threading into openings 24 of the head. This extension has a substantial sealing engagement at 22 with a thimble 26 inserted in the inner end closure 21 of easing l0 and surrounding the air inlet opening 22 of such closure. The extension 22 and head 2| are provided with semi-circular seats 22 receiving valve casings 40. Valve casings 42 are each in the form of a thimble, the outer end of which is closed and the inner end of which is in communication. with the compartment defined by the valve casings, head, and extension 1 22, and the head is provided with a conical extension 4| which will direct air entering through inlet 22 into the inner ends of these casings. The ports 42 of the valve casings open to the compartment at the exterior of the head and, accordingly, are in communication through the ports of bushing 22 and washer 21 with the inlet l2 of the motor cylinder. These ports are controlled by valves 42 each comprising upper and lower ring elements 44 connected by radial ribs .a socket 48 formed in the outer wall of the valve casing. Inward movement of the valves is limited through engagement with the seats for the valve casing, I

It will be obvious that by properly proportioning the strengths of spring 41 and the weight of valve 42 these valves can be. caused to move radially under centrifugal force to close the ports 42 when a predetermined rotor speed is attained by rotor 22.

Obviously, a construction of this type may be incorporated, while utilizing very slightly more than the waste space ordinarily provided between the inner end of head- 2| and the enclosure member 21, in the u'sualtube cleaner motor construction, and a governor of the type shown will be sufllciently accurate to maintain the speed of the motor within a safe operating range. Obviously, under these circumstances it likewise becomes possible to utilize higher pressures, thus eliminating stalling of the motor under what would normally be overload conditions where the pressures utilized must be kept low enough to insure against damaging operation in event the conditions become such as have been hereinbefore pointed out.

In the form shown in Figs. 11 to 15, the head.

2|a is provided with a tubular extension 42 the outer end of which is provided with a flange II having sliding engagement with the thimble 26. The tubular extension 42 has radial slots 5| which are controlled by sleeve valve 52 mounted for oscillation about the tubular extension 42 and having ports 52 for registration with slots 2| of 'the extension.

Within the inlet compartment formed by the extension 49 and head 2|a is a pair of bell crank weight arms 54, the lighter arms 55 of which project through slots 56 in the extension 42 and are provided with rounded heads engaging in openings 51 formed in the sleeve valve 2. Radial movement of the heavier arms is opposed by springs 58, and the arrangement of the parts is preferably such that, assuming the direction pressure supply at such sudden increases of speed, thus preventing dangerously rapid rotation of the motor when extremely light scale is encountered, or the motor is accidentally projected from the far end of a tube being cleaned.

The pivots for the bell crank arms 54 comprise pins 59, cottered, or otherwise secured against longitudinal movement with relation to the head, as indicated at 60. These pins serve at their inner ends as a mounting for a cone-shaped projection 6| which serves the dual function of defleeting the incoming air toward the governor ports and to prevent the incoming blast of air from exerting flow head-pressure on the governor-weights, which would tend to impede the operation thereof by causing excessive frictional engagement with the head.

In the form of invention shown in Figs. 16 to 20, the head 2|b has a pair of. outwardly projecting arms 62, the outer ends of which are connected by a cross bar 63, the purpose of which will presentlyappear. The outer surfaces of these arms are curved upon a common radius coaxial with the axis of the extension 26 and fittingly receive the inner end of a sleeve 64 the outer end of which is flanged to sealingly engage the thimble 3B. This sleeve is provided with radial slots 65 and upon its exterior has mounted a sleeve valve 66 which is similarly slotted as indicated at 61. The arms 62 have openings 68 mounting pins 69 which, in turn, mount bell crank weight arms the heavier arms ll of which are directed longitudinally of the compartment formed by the head and sleeve and are normally urged inwardly through the medium of governor springs I2. The lighter arms project through slots 13 formed in the sleeve 64 and have rounded heads engaging in openings 14 in the sleeve valve 66. In this form the sleeve valve is, upon outward movement of the weight arms II, shifted longitudinally upon sleeve 64 to close the ports 65. In order to direct the air outwardly to these slots as in the previous constructions, and to prevent interference for the blast of incoming air with the governor arms,

the outer ends 15 of arms 62 are formed as fragmentary surfaces of a common cone. The connecting arm 63 is inset slightly from the outer extremity of the arms, as more clearly shown in Fig. 20, and a curved shielding plate 16 bridges the gap between the arms and has its ends engaged in-slots 11 formed in the sleeve. Such plate substantially completes the conic surface partially defined by the ends 15 of the arms.

In addition to the graduated closing afforded by radial movement of valves of the same weight opposed by springs of the same strength as suggested inthe form shown in Figs. 1 to 15, the graduation as to effective port area can be further controlled by making the springs of different characteristics. This may be either by making all of the springs of the valve units of difierent characteristics, as shown at 41a, 41b, 41c, and lid in Fig. 21, or by arranging the valve units in groups, each group being controlled by springs of the same characteristics, as indicated at "e and 41! in Fig. 2. While, for the sake of illustration, I have shown the springs themselves as employed to control the closing time, and such structure is. obviously mechanically preferable, this end may likewise be accomplished by varying the weight of the valve unit proper.

As will be noted from the illustration, the port area provided by the various centrifugally controlled valves is at least equal to, if not in excess of, that provided in the motor supply duct II, with the result that the motor has a full supply upon maximum demand, while at he same time the governor has control of the motor at any time that it may arrive at an excessive speed. These conditions are met by providing the motor shaft with the enlarged heads present in each of the forms illustrated so that an increased area for port formation is afforded.

It will be understood that while I have referred to engagement with the thimble 38 as being a sealing engagement, this engagement need only be such as to substantially seal the joinder between the thimble and head since a slight leakage would be in no way critical. It will also be understood that the several modiflcations hereinbefore illustrated are merely specific examples of my invention and I, accordingly, do not wish to be understood as limiting myself to the constructions herein described excent as hereinafter claimed.

I claim:

1. The combination with a high speed tube cleaner motor comprising a cylindrical casing of small diameter, means dividing the easing into supply and motor chambers having port communication with one another, a rotary motor in the motor chamber including a cylinder having a large supply port in communication with the supply chamber, a rotor shaft projecting into the supply chamber and an enlarged head on the shaft within the supply chamber, the supply chamber having an axial inlet port, of an annular means on said head having substantial sealing engagement with the peripheral wall of the inlet port and dividing said supply chamber into primary and secondary compartments of which the secondary compartment is in constant communication with the supply port of the motor chamber, said annular means having ports to place said compartments in communication with one another, said ports being arranged on an approximate diameter considerably in excess of the diameter of the shaft and having a combined maximum area at least as great as the supply port of the cylinder, and centrifugally controlled means carried by the head and first-named means for controlling the area of said ports.

2. A device as claimed in claim 1 wherein the centrifugally controlled means comprises radially movable valves.

3. A device as claimed in claim 1 in which the means on the head comprises a longitudinally slotted sleeve and the centrifugally controlled means comprises a valve rotatable on said sleeve.

4. A device as claimed in claim 1 wherein the means on the head comprises a circumferentially slotted sleeve and the centrifugally controlled means comprises a longitudinally movable sleeve valve mounted on said sleeve.

5. A device as claimed in claim 1 in which the centrifugally controlled means comprises a plurality of radially extending valve casings each having a spring-opposed radially movable valve therein, said valve casings having their inner ends opening to the primary compartment and having ports controlled by the associated valve opening into the secondary compartment.

6. A device as claimed in claim 1 in which the centrifugally controlled means comprises a longitudinally slotted sleeve secured to and rotating with the head, a second longitudinally slotted sleeve oscillatable about the first-mentioned sleeve, means normally holding said sleeves with the slots thereof in alignment and centrifugally controlled means to shift said second sleeve and move said slots out of alignment at predetermined rotative speeds of said head.

7. A device as claimed in claim 1 wherein the centrifugally controlled means comprises a circumferentially slotted sleeve secured to and rotating with said head, a longitudinally slidable sleeve mounted upon the first-named sleeve and likewise having circumferential slots, and centrifugally controlled means for longitudinally moving the last-named sleeve.

PAUL I. GOOD. 

